• Transactions of the Korean Society of Mechanical Engineers B
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• v.36 no.7
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• pp.759-765
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• 2012

This study investigates the effect of diesel combustion strategies on exhaust emissions and hydrocarbon species emissions for a 1.7 L common rail direct injection diesel engine at 1500 rpm and 3.9 bar BMEP. The first strategy is a method to adopt no EGR with a split injection composed of pilot and main injection (split injection). The second is to adopt a moderate EGR rate with main injection only (single-1). The third is to use a high level of EGR and main injection with rail pressure increase, $i.e.$ low-temperature diesel combustion (single-2). Split injection and single-1 showed a renowned phenomenon of a PM-NOx trade-off, whereas single-2 was observed of a PM-NOx trade-off to reduce PM and NOx simultaneously. HC speciation results show that the split injection produced the least amount of HC species, regardless of the carbon number bin, followed by single-1 and single-2. The ratios of methane, acetylene, and CO to THC increased as a combustion A/F ratio is richer due to reduced oxygen content in the vicinity of the combustion zone, thus enhancing pyrolysis.

• The Korean Journal of Petroleum Geology
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• v.11 no.1 s.12
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• pp.27-41
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• 2005

The hydrocarbon source rock potential of the Eocene units in the southern Oregon Coast Range was evaluated by using the Rock-Eval pyrolysis. Most Eocene units in southern Oregon Coast Range are thermally immature and contain lean, gas-prone Type III kerogen. However, some beds(coals) are sufficiently organic-rich to be sources of biogenic and thermogenic methane discovered in numerous seeps. The overall hydrocarbon source rock potential of the southern Oregon Coast Range is moderately low. Several requirements for commercial accumulations of hydrocarbon, however, probably exist locally within and adjacent areas. Three speculative petroleum systems are identified. The first includes the southern part of the Oregon Coast Range near the border with the Mesozoic Klamath Mountains and is related to a proposed subduction zone maturation mechanism along thrust faults. The second is centered in the northern part of the range and may be associated with basin-centered gas in an over-pressured zone. The third occurs near the eastern border of the range where maturation is related heating by sills and migration of hydrothermal fluids associated with mid-Tertiary volcanism in the Western cascade arc.

• Journal of the Korean Chemical Society
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• v.40 no.9
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• pp.615-622
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• 1996

(Benzotriazol-1-yl)arenesulfonylalkanes, 2a, 2b, 3a and 3b, were prepared by lithiation of 1-(benzotriazol-1-yl)arenesulfonylmethanes followed by reaction with alkyl iodides. Very bulky molecules such as 1,1-di(benzotriazol-1-yl)-1-aryl-1-thiophenoxymethanes 5, 1,1-di(benzotriazol-1-yl)-1-thiophenoxymethane 9a and 1,1-di(benzotriazol-1-yl)-1,1-dithiophenoxymethane 9b were synthesized. 1,1-Di(benzotriazol-1-yl)-1-benzenesulfoxymethane 10a and 1,1-di(benzotriazol-1-yl)-1-benzenesulfonylmethane 10b were also synthesized by the oxidation of compound 9a, while oxidation of sulfide group on compound 5 and 9b by m-CPBA were not successful. On the other hand, pyrolysis and hydrolysis of 3-(benzotriazol-1-yl)-3-toluenesulfonylpentane 3b gave 3-toluenesulfonyl-2-pentene 11 and diethyl ketone 13a, respectively, which means there are both C-N and C-S bond cleavages.

• Journal of Korean Society of Environmental Engineers
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• v.29 no.9
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• pp.1027-1034
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• 2007

This research was focused on the selective separation of $CO_2$ or $CH_4$ from mixture of these gases, by controlling the size of pore or pore gate. Pitch based activated carbon fibers(ACF) were used as adsorbents. The size of pore gate was controlled by the molecule having similar size to that of pore opening. After the adsorption of adsorbate on pore surface, planar molecules such as benzene and naphthalene covered the pore gate. The slow release of adsorbate from the pores covered by planar molecules makes apertures between planar molecules covering pore gate and this structure can be fixed by rapid pyrolysis. The control of pore gate using benzene as covering molecules could not accomplished due to the simultaneous volatilization of benzene and adsorbate$(CO_2)$ caused by similar temperatures of benzene volatilization and adsorbate desorption. Therefore we replaced benzene with naphthalene looking for the stability at a $CO_2$ desorption temperature. The naphthalene molecule was adsorbed on the ACF up to 15% of ACF weight and showed no desorption until $100^{\circ}C$, indicating that the molecule could be used as a good cover molecule. Naphthalene could cover almost all the pore gate, reducing BET surface area from 753 $m^2/g$ to 0.7 $m^2/g$. A mixed gas$(CO_2:CH_4=50:50)$ was adsorbed on the naphthalene treated OG-7A ACF. The amount of $CO_2$ adsorption increased with total pressure, whileas thai of $CH_4$ was not so much influenced on the pressure, indicating that $CO_2$ made more compounds on the ACF surface along with total pressure increase. The most $CO_2$ and the least $CH_4$ were adsorbed in the condition of 0.4 atm, resulting in the highly pure $CH_4$ left in ACF.